Surely some of you must have a checklist...?
Your mental checklist you run through before each move.

1. If I have the initiative, how can I add more pressure
2. What are the imbalances in the position.
3. how can I take advantage of my oppenent weaknesses in his position and the same time solve my weaknesses
4. How can i reach a winning endgame.
5. Go for the KILL!

http://www.chesscafe.com/archives/archives.htm#Novice%20Nook
There's an article near the bottom of Novice Nook Archives called "Real Chess, Time Management, and Care" that addresses this pretty good. It's helped me to play slow games better because I used to always play fast and never developed an organized thought proccess. It makes a difference when you are thorough and use up your clock to think things through.
Also I found this on someone's blog (http://lousyatchess.blogspot.com/2008/07/what-should-i-do-when-my-opponents.html) where Mikhail Botnivikk tells what he does while his opponents clock is ticking:
"In his book, Think Like A Grandmaster, Alexander Kotov posed a similar question to Mikhail Botvinnik.
Botvinnik's reply was very insightful.
"Basically I do divide my thinking into two parts. When my opponent's clock is going, I discuss general considerations in an internal dialogue with myself. When my own clock is going, I analyse concrete variations."

I dont use a checklist. If you're using a checklist then you're not thinking about chess, you're thinking about you're checklist. I always try to understand my opponents thinking behind each of his moves. This will usually clear up any of those nasty little amature mistakes like leaving pieces to be captured for nothing, or missing a combination. I take my time, and just look at the board..not really thinking about anything, but just letting it come to me..even if it takes 20 minutes. There is no secret formula or secret thinking method. You just have to know the material. The more you know, the less you will not know, and the less you dont know, the better your chances of knowing more then you're opponent, and therefore increasing you're chances of winning. Simple.

Stankwagon, you're definitely welcome to your opinion, but I 100% disagree with your statements surrounding checklists equating to "not thinking about chess". There are many things to consider when making a move in chess. Just blankly staring at the board and letting your moves "come to you" does not bode well for consistent disciplined play.
Having a checklist to help remind you of the different concepts you want to look for is hardly a negative for your game, as it forces you to consider all aspects, rather than letting your brain stop short of all considerations in favor of a candidate move you simply can't stop drouling over.
Cheers.

In correspondence chess, I use a pre-checklist checklist:
- which colour am I playing?
- am I winning or losing?
- which piece did my opponent just move?
- which piece did I last move?
- what was I thinking of??

@ stankwagon and wiseachoo, there is nothing wrong with your idea ,maybe bit of both idea might work and is all depending how one's ability to think sometime you can,t go through the checklist because of time pressure but it is helpful though.

When I joined this site in February, if my opponent attacked a piece, i.e. a pawn attacking a bishop, my likely response would be to have moved that piece. Now, I always look for a possible counter attack. Is there somewhere I can move, where if he takes that piece, I can recapture and leave him at a positional/material disadvantage.
Just one of the ways I think my place has improved since I joined this site having not played chess in many years before.

I obviously need some kind of checking system, because I just played a move in a game where I needed to play another move first. Having seen this, I kind of just assumed I'd do it, and worked on the rest of the variation, then promptly forgot to play the vital first move. Now my position is (potentially) ruined - as long as my opponent sees the problem, that is.

It's too lengthy if I discuss my thoughts here. I wrote a blog with a title MOVE SELECTION PROCESS. Please read if you have time. tnx.
http://blog.chess.com/Gokukid/move-selection-process

Years ago my buddies told me to begin by looking for every possible check and capture.
I've tried many times to make a checklist but it always gets sooooo long - hanging pieces - discovered attack - pins - skewers - forks - removing defender - decoys - x ray - kicking him under the table - (I always forget to look for smother mates) - and first on my checklist - trying to remember what was that brilliant plan I had before he made his last move?

I generally just think along the lines of -
What am I trying to do?
What is my opponent trying to do?
What do I want my opponent to do?
What is my opponent trying to make me to do?
I then compare what I'm trying to do with what my opponent is trying to do, if I have a time advantage I can often ignore what my opponent is tryign to do, if I don't have a time advantage I try to avoid doing what my opponent wants me to do while bringing me closer to what I'm trying to do.
Of course this sort of checklist doesn't really stop me from blundering. But playing out each move on the analysis board generally does.

I see a lot the recommendation to think about "What did my opponent's last move attack, what is he trying to accomplish" and these are important to ask, but don't forget to think "what did my opponent's last move just weaken". Often times we are focused on our plan and when our opponent moves we forget that a new plan might be available. When your opponent moves a piece that pieces may no longer be defending the pieces or squares it used to defend. While making your plan previously you may have ruled out plans that require the use of these squares. Don't forget to consider those plans now!
The same checklist that you think of after your opponent's move is useful when analyzing the position after your potential moves. What does this move attack, what does my opponent have to respond to after I make this move, what in my position does this move weaken?

Diskamyl, great find from the other message board on a structured checklist. Boy that thing is LONG! For those too lazy to check out the other thread, here's another list originally pulled from RedHotPawn message boards:
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I. Analyze the board every move using the following system:
1. Take a look at the board with fresh eyes, setting aside, for the moment, my plans, expectations, and concerns about the position that I had on my last move. Ask myself the following questions:
(a) Are any of my pieces undefended or hanging?
(b) On my opponent's next move, can he create a strong pin or exploit an existing one?
(c) Can he fork any of my pieces (pay attention to pawn and N forks as they are easiest to miss).
(d) Does he have any discoveries or double attacks?
(e) Does he have any potential checks and if so, how do I meet them?
2. Having run down that list, what does his last move then threaten?
3. Turning to what I can do on my move, run through the list a-e to determine if I can win material on my move, setup a combination, or strong initiative. Now ask myself, whose threat is stronger? If his is stronger, then find the move that best meets or parries his threat. The ideal move, if I must defend, should also setup a threat of my own or create some other complication.
4. Either way, write down the candidate move(s) and, going through each move once and once only, make it on the analysis board. Pay attention to the resulting new position, and whether attacking, counter-attacking, or defending, keep the the following in mind:
(a) What is his most likely response to my threat, sacrifice, capture, check, or defensive move?
(b) Has my move left a previously defended piece exposed to capture or exposed my K to a check I can't meet?
(c) Has it dangerously weakened my position?
(d) Does he have any surprise resources?
5. If several moves are involved in a sequence, work through each move on the analysis board repeating each of the steps in (4). Work through variations once and once only. Use a tree to keep it organized and terminate each variation with a short, concise and honest evaluation.
6. If no forcing sequences, threats or combinations exist, look for quiet moves aimed at improving my position and or weakening/cramping my opponents. Candidate moves should do one or more of the following:
(a) Increase my hold on the center.
(b) Increase the pressure on whichever sector of the board I am attacking.
(c) Create or increase the pressure on a weakness in my opponents position.
(d) Open lines for my pieces.
(e) Increase the mobility/activity of my less active pieces.
(f) Restrict the mobility of my opponents pieces.
(g) Create strong squares that my pieces can exert pressure from and from where they cannot be easily chased away.
(i) Create (protected) outposts in my opponents camp.
(j) Improve my pawn skeleton with the idea of creating the conditions of the previous goals and/or the (future) creation of a passed pawn.
(k) Keep in my mind that middle games can suddenly become endgames. Were this to happen now, would it be decisive? If it would, and in my favour, work toward exchanging toward the endgame. If it wouldn't, avoid those types of exchanges and either try to improve my endgame prospects or bet the farm on the middle game.
(l) Where an exchange of pieces is offered or possible, ask myself who benefits from the exchange? Which piece is more active? Does either piece play a key role in either attack or defence? If its a N, does it have valuable outposts it can occupy? If a B, is it the "good" or the "bad" B.
II. Play regularly to stay sharp, but not to excess which will only lead to sloppiness. Avoid playing too much blitz.
III. Analyze and annotate RHP games after they're over with the written notes made during the game at hand. Compare your analyzed variations and evaluations with the actual moves made in the game. What did you overlook and why? Were your evaluations accurate? After you've done the initial analysis the old-fashioned way, run the game through an engine to see what you missed and to get an objective comparison of evaluations that you can compare to your own.
IV. After you've completed your analysis, play through at least one Master level game that followed the same line (however far it was followed) as was played in your game. Choose a game where the colour you played either one or drew. Play through it as though you were that player, covering the moves your player made and deciding for yourself what you'd move before seeing what was played. Try to figure why the move played was stronger than the one you'd chosen. If time permits, play through another game in the same line where your colour lost. This time just try to determine why the losing player lost.
V. Analyze the opening phase of your blitz games and the opening phase only. There is no point in spending an hour going over a game you played in 5 minutes. There is a point, however, in following it up until it departed book and determining if the non-book move was bad, why it was bad, or if it was sound enough but just not fashionable. Look a little further into the line with an opening book or database to expand your knowledge of that variation. If time permits, quickly play through (in 5 minutes or so per game) a few Master level games that were played in this line.
This time you're not attempting to find the best moves, or why, but merely to get a feeling for the flow of the game. What kinds of tactics were used? Pawn structures? Which wing of the board did each side concentrate on? How did they occupy or control the center? What kinds of flank pawn moves were made? Did they castle same side or opposite side? Were pawn storms used or mainly piece play? Was a minority attack employed? A mating attack? What was the general plan from each perspective and can you spot any thematic moves or sequences aimed at realizing that plan? Doing this will increase your understanding of the opening and help you avoid situations where you're stuck wondering what to do, or simply chose plans and moves that are at odds with the focus of the opening.
VI. Be graceful under fire. Remember its just a game, you are not a Kasparov, a Tal, or a Capablanca. Its not whether you win or lose that matters, but what you put into the game and what lessons you can take away from it.
VII. Expand your knowledge of the crucial elements of the game tactics, endings, strategy, openings - by drawing on the great chess literary works. And remember that chess is a game that is played with all elements as a whole, and not in isolation, and therefore complete, well annotated games must not be neglected if one is to understand the interplay of the elements.
addenda:
(I) 3a. Can I sacrifice any of my material to open up lines for attack, create a strong initiative, mate my opponent, or win the material back with interest.
(I) 4d. Does he have any surprise resources, including moves that superficially appear "bad", even to lose material, but which completely refute my attack or turn the tables on me?
(I) 5. If several moves are involved in a sequence, work through each move on the analysis board repeating each of the steps in (4). Work through variations once and once only, but carry the analysis one move farther than "common sense" dictates it should end. Use a tree to keep it organized and terminate each variation with a short, concise and honest evaluation.
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I think the anti-blunder checklist is pretty simple -- don't move until you've found your opponent's best reply and you have a satisfactory answer to it. The problem of course is that we get tunnel vision and we examine one or two obvious replies rather than really scouring the board for the opponent's best reply. If you discipline yourself to think as hard and creatively for your opponent as you do for yourself I think you can do without any checklist.
I've started to reach the conclusion that I need to force myself to go through a disciplined list of thoughts before deciding on a move, much like many of the books in my collection have hinted at. I thought it would be very beneficial to compare and contrast this mental checklist between those less experienced and those more experienced.
Obviously, over time you wouldn't necessarily refer to a literal physical list before each move, as you've trained yourself to ask the questions in your mind. I'll get this thread started with a list that I put together for myself earlier in the week that actually helps a lot IF I force myself to use it.
Questions I ask myself before making a general move:
Questions I ask myself when I am in check and about to make a move: